1. Field of the Invention
The present invention relates generally to diamond foam heat sinks and more specifically it relates to a diamond foam spray cooling system for improving the thermal management of a heat producing device.
2. Description of the Related Art
Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
FIG. 1a illustrates a conventional spray cooling thermal management unit (A) that is comprised of a housing (C) forming a chamber (E) with a heat spreader (B), wherein the heat spreader is thermally attached to a heat producing device (H) by a thermal interface material (G). As further shown in FIG. 1a, a spray assembly (F) within the thermal management unit sprays liquid coolant upon the cooling surface of the heat spreader for thermally managing the heat producing device.
FIG. 1b illustrates another conventional spray cooling thermal management unit (A) that is comprised of a housing (C) forming a chamber (E) connected directly to the heat producing device (H). As further shown in FIG. 1b, the spray assembly (F) within the thermal management unit sprays liquid coolant directly upon the heat producing device.
FIG. 1c illustrates a diamond heat spreading and cooling technique for integrated circuits as disclosed in U.S. Pat. No. 6,667,548. FIG. 1c illustrates a heat producing device (H) with diamond foam (I) directly attached, wherein the diamond foam is thermally attached to a heat spreader (J) by a thermal interface material (G) and wherein a conventional heat sink (K) is attached to the heat spreader.
Natural diamond has a high thermal conductivity of approximately 1,800 watts per meter-Kelvin (W/m-K). Chemical vapor deposition (CVD) processes have been developed to create “diamond foam” that has a polycrystalline structure having a high thermal conductivity approaching that of natural diamond (typically between 1000 to 1800 W/m-K). CVD processes for creating diamond foam are well-known in the art as discussed in U.S. Patent Application Publication No. 2003/0118827 which is hereby incorporated by reference. CVD diamond foam is currently used in traditional heat sinks and heat spreaders in applications such as laser diodes, semiconductors and other heat producing devices. Conventional cooling methods are used to then transfer the conducted heat from the CVD diamond foam such as air cooling as illustrated in U.S. Pat. No. 6,667,548.
While diamond foam may be suitable for traditional heat conductivity applications, diamond foam's heat conductivity is limited by the ability to remove the conducted heat from the diamond foam itself. Hence, there is a need for a thermal management system that efficiently utilizes the unique heat conductivity properties of diamond foam to thermally manage a heat producing device.